Hydrangeas are popular garden shrubs, prized for their large, showy blooms. While generally safe to handle, understanding their properties is important for household safety. The primary concern is not casual contact, but the risk of internal poisoning if any part of the plant is consumed. This systemic risk associated with ingestion is far more serious than the localized, minor risk of touching the plant.
Are Hydrangeas Toxic to the Skin?
Touching a hydrangea plant is not typically dangerous, and most people can handle the flowers and leaves without reaction. However, all parts of the plant contain mild irritants that can cause a localized reaction in sensitive individuals. This reaction is a type of contact dermatitis, which is a mild skin inflammation.
Symptoms of this irritation include localized redness, itching, or a mild rash where the plant material has rubbed against the skin. These issues are usually mild and temporary, resolving quickly once the skin is washed. Contact with the plant’s sap, especially during pruning, may increase the chance of a reaction due to a higher concentration of irritants.
Systemic Risks: Why Ingestion is Dangerous
The true danger of the hydrangea plant lies in its systemic toxicity if any part, including the leaves, buds, or flowers, is ingested. This hazard is due to the presence of compounds known as cyanogenic glycosides, specifically the chemical hydrangin. When these compounds are chewed or digested, the body’s enzymes break them down to release hydrogen cyanide (HCN).
Hydrogen cyanide is a potent poison that interferes with the body’s ability to use oxygen at the cellular level. Ingestion usually results in gastrointestinal distress, the most common sign of hydrangea poisoning. Symptoms often include nausea, vomiting, diarrhea, and stomach pain in both humans and animals.
Consuming large quantities of the plant can lead to more severe systemic effects. These signs may include lethargy, weakness, and breathing difficulties. In extreme cases, particularly in small children or pets, massive ingestion can potentially cause respiratory distress, convulsions, or coma. Anyone who suspects a person or pet has eaten a part of a hydrangea should seek immediate medical or veterinary advice.
Safe Handling and Precautionary Steps
Exercising simple precautions ensures safe interaction with hydrangeas for gardeners and homeowners. For those pruning or harvesting large amounts of the plant, wearing long sleeves and gloves provides an effective barrier against the irritating sap. This practice minimizes the risk of developing localized contact dermatitis from prolonged exposure.
Wash hands thoroughly with soap and water immediately after handling any plant material. This removes residual sap or irritants, preventing accidental transfer to the eyes or mouth. Since ingestion presents the most serious risk, pet owners and parents should ensure hydrangea plants are placed in areas inaccessible to curious children or foraging animals. Using physical barriers, such as a low fence, can help separate pets from the plants in a garden setting.